“…Several authors reported that the carboxylic-end of the amino acids [12,13,[22][23][24][25][26][27] and polymers [28][29][30][31] bind to a metal-oxide particle or film surface through chemisorption by bidentate bonding between the carboxylic group of the additive (aminoacid/polymer) and the metal atoms on the metal-oxide surfaces. Hence, it is likely that here also the negatively charged carboxylic groups ( Fig.…”